SEOUL, South Korea >> South Korea and the European Union on Monday strongly condemned North Korea’s reported dispatch of troops to aid Russia’s war against Ukraine and expressed concerns that Russia could reward North Korea with transfers of sensitive technology to enhance its nuclear and missile programs.

North Korea’s troop deployment, confirmed by the U.S. and NATO, threatens to expand the almost 3-year-long war and is causing security jitters in South Korea and elsewhere about what Russia could give North Korea in return.

After a meeting in Seoul, South Korean Foreign Minister Cho Tae-yul and EU foreign policy chief Josep Borrell issued a joint statement condemning in the “strongest possible terms” North Korea’s deployment and voicing worries about Russia’s possible provision of materials and technology to North Korea in support of its military objectives.

“We are also deeply concerned about the possibility for any transfer of nuclear- or ballistic missile-related technology to the DPRK, which would jeopardize the international non-proliferation efforts and threaten peace and stability on the Korean Peninsula and across the globe,” the statement said. DPRK stands for the Democratic People’s Republic of Korea, North Korea’s official name.

Cho and Borrell called North Korea’s deployment a “flagrant” violation of multiple U.N. Security Council resolutions and called on North Korea and Russia to immediately withdraw the troops from Russia.

Also on Monday, in Moscow, Russian President Vladimir Putin met North Korean Foreign Minister Choe Son Hui, who has been on an official visit to Russia since late last week.

State television showed them greeting each other, but details of the meeting were not available.

Earlier Monday, Borrell met South Korean Defense Minister Kim Yong Hyun and they agreed to work together with the international community to try to obstruct Russian-North Korean security cooperation, according to the South Korean Defense Ministry.

North Korea and Russia haven’t explicitly confirmed the North Korean deployment. But they’ve both argued that their military cooperation conforms with international laws.